Burner nozzle



G. A. FISHER BURNER NOZZLE Oct. 23, 1951 Filed Sept. 9, 1947 w M fig 1 W .m AL. W U

a. 5 4 M M n 3 M\ 7 n/A MM 6 INVENTOR. 6594x06 fZsy/fi BY Patented Oct. 23, 1951 BURNER NOZZLE Gerald A. Fisher, South Bend, Ind., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application September 9, 1947, Serial No. 772,971

4 Claims.

This invention relates to burner nozzles for supplying fuel to the burner system of a gas turbine engine. In such systems there may be a relatively large number of nozzles receiving fuel under a wide range of pressures from a common fuel manifold and discharging the fuel in atomized form into a series of burner or combustion chambers individual to the respective nozzles or a single combustion zone or chamber common to all nozzles. In order to insure an eflicient discharge spray over the entire pressure range, it is common practice to use a manifold system incorporating burner nozzles wherein the fuel at low manifold pressures is discharged through one or more restricted orifices or passages, and at higher manifold pressures through additional orifices or passages of increased flow capacity. As heretofore constructed, however, such systems involved more or 16 complicated manifolding, and it is an object of the present invention to provide a burner nozzle which will function effectively over the entire pressure range with a single manifold and which at the same time will give long trouble-free service, is of simplified construction and embodies a minimum of moving parts.

Another object is to provide a nozzle of the type specified having an inbuilt control valve which is the only moving part of the nozzle, the arrangement being such that counterflow at low pressures is prevented while at the same time the valve has freedom of movement at all conditions of operation and is readily accessible for adjustment.

The foregoing and other objects and advantages will become apparent in view of the following description taken in conjunction with the drawings, wherein:

Figure l is a substantially central longitudinal sectional view taken through a nozzle constructed in accordance with the invention;

Figures 2, 3 and 4 are cross-sections taken on the lines 2-2, 3-3 and 4-4, Figure 1;

Figure 5 is an enlarged sectional view of the nozzle tip; and

Figure 6 is a detail elevation of a valve seat member constituting one of the parts of the nozzle assembly.

Referring to the drawings in detail, a nozzle body or outer shell is generally indicated at I2); it is of elongated hollow cylindrical form and provided with an external flange l I and a screwthreaded portion l2, by means of which it may be mounted in operative relation to a burner or heat generator, not shown. The discharge end of the body or shell converges in frusto-conical form defining a, seat or retainer for a nozzle tip, to be described. The hollow interior or chambered area l3 of the nozzle body is adapted to receive a sleeve-like member l4 which at its one extremity is formed with a grooved annulus l5 adapted to receive a sealing ring l6. Within the sleeve is a chamber H terminating forwardly in a reduced portion or bore defining a passage ll.

An annular groove I8 is formed in the sleeve I4, the adjacent surface of the annulus l5 defining a wall of said groove. At its outer solid end, the surface of the sleeve I 4 has a shallow axial groove I9, and a series of small or fine bores or passages 20 communicating the annular groove l8 with the axial end groove IS. A series of radial bores or passages 2| communicate the end of the passage l'l' with a chamber 38 through the end of the sleeve, the chambers l3 and 38 being sealed off by the seal ring 16. The end of the sleeve l4 opposite the discharge end of the nozzle is enlarged at 22 and formed with flattened portions 23 through which are drilled orifices or radial passages 24 by means of which fuel is communicated to the chamber I3 at manifold pressures.

A valve 26 is mounted in the chamber ll; it is preferably of the ball or spherical type and is urged towards seated position by a spring 21. The valve 26 controls admission of fuel into the chamber I! through a passage 28 formed in a valve seating sleeve member 29 terminating in a valve seat 29', said sleeve member having an annularly reduced portion defining a chamber 30 to which fuel may flow from the passage 28 by way of holes or orifices 3|. The inner end of the valve seating sleeve 29 is formed with an enlargement which is annularly grooved to receive a sealing ring 32, the latter sealing ofi chamber 30 from chamber or passage H. The valve seating sleeve 29 is externally/screw threaded in order that it may be threaded into the sleeve H, the outer end of said sleeve being slotted to facilitate adjust ment of the seat within the sleeve.

A nozzle tip 33 (see Figure 5) is seated in the discharge end of the body l0, said tip being formed With a flared discharge orifice 34 in rear or upstream of which is a swirl chamber 35. The body portion 36 of the tip is formed with a series of radial passages 3! which communicate fuel from the chamber 38 to the swirl chamber 35, the said passages 31 being formed at a'tangent to said swirl chamber. The inner end surface of the tip is in flush contact or seating engagement with the adjacent axially grooved end of the sleeve 14, and said surface is formed with a pair of tearand direct it into the swirl chamber 35, the said slots being also formed at a tangent to the latter chamber.

A lock ring 4| retains the valve seating sleeve 29 in adjusted position; and an externally-flanged retainer ring or nut 42 holds the sleeve l4 in place, the retainer 42 being locked against displacement by an elongated end member 43 which is hollow to provide a continuation of the passage-28 and has fitted therearound a filter 44 through which fuel flows and thence by way of radial passages 45 to the axial passage 28.

Operation In operation, fuel under pressure from a fuel manifold or the like, not shown, enters the passage 28 through the filter 44 and inflow ports 45,

and up to, for example, twenty p. s. i., the fuel and slots 39. Since the discharge portions of these slots are greatly restricted, the low pressure or idle fuel will enter the whirl chamber at a relatively high velocity and be discharged from the nozzle tip through the flared discharge opening 34 in the form of a divergent or cone-shaped spray. When the manifold pressure rises above a predetermined value, say for example twenty p. s. i., the ball check valve 26 unseats, whereupon fuel will flow through the high pressure flow passage defined by the chamber ll, passage ll, radial ports 2|, chamber 38 and radial port 3'! to the whirl chamber and be discharged from the nozzle opening 34 along with the low pressure fuel. Thus, the discharge spray will be well projected over a relatively wide range of fuel pressures, eliminating nozzle drip at low pressures, facilitating starting, and producing other advantages inherent in duplex manifold systems.

The improved nozzle has all of the advantages inherent in duplex supply systems while at the same time it utilizes only one manifold and does not require separate control valves, either automatic or manual. When operating under idle fuel pressures through the small slots 39, counterfiow back through the passage 28 is prevented by the valve 26, the seat of which is readily adjustable to in turn adjust the spring 21 and thereby determine. the opening pressure of said valve. The parts are readily accessible for cleaning, and may be manufactured at a relatively low cost considering the precision work required on certain of the parts.

Although only one embodiment of the improved burner nozzle has been illustrated and described, certain changes in the form and relative arrangement of the parts may be made to suit requirements.

I claim:

1. A burner nozzle comprising a nozzle body having a nozzle tip at the discharge end thereof, said tip being formed with a discharge orifice and a whirl chamber in communication with said oriflee, said tip being also formed with separate inflow ducts for conducting low pressure and high pressure fuel to said whirl chamber, said low pressure ducts being restricted to impart high velocity to the fuel at relatively low fuel flows, a hollow valve housing located within the nozzle body and spaced therefrom to provide a low pres- 4 ducts, the interior of said valve housing providing a high pressure flow passage leading to said high pressure ducts, a valve seat removably disposed within said housing and formed with a flow pasengaging said seat, said nozzle having means defining a single inlet passage for liquid fuel upstream of said check valve common to said low and high pressure fuel passages.

2. A burner nozzle comprising a nozzle body having a nozzle tip removably seated in the discharge end thereof and formed with a .discharge orifice and a whirl chamber in communication with said orifice, said tip being also formed with separate inflow ducts for conducting low pressure and high pressure fuel to said whirl chamber, said low pressure ducts being restricted to impart high velocity to the fuel at relatively low fuel flows, a hollow valve sleeve located within the nozzle body and spaced therefrom to provide a low pressure fuel passage leading to said low pressure ducts, the interior of said sleeve providing a flow passage leading to the high pressure ducts, a valve seating member removably and adjustably disposed within said sleeve and formed with a flow passage communicating with said high pressure passage through a valve port, and a spring pressed check valve controlling said port, adjustment of said seating member effecting ad- Justment of said valve.

3. A burner nozzle comprising a nozzle body having a nozzle tip removably seated in the discharge end thereof and formed with a discharge orifice and a whirl chamber in communication with said orifice, said tip being also formed with separate inflow .ducts for conducting low pressure and high pressure fuel to said whirl chamber, said low pressure ducts being restricted to impart high velocity to the fuel at relatively low fuel flows, a hollow valve sleeve located within the nozzle body and spaced therefrom to provide a low pressure fuel passage leading to said low pressure ducts, the interior of said sleeve providing a flow passage for high pressure fuel leading to the high pressure ducts, a valve seating sleeve removably and adjustably disposed within said valve sleeve and formed with a flow passage common to both said low and high pressure passages, said seating sleeve terminating in a valve seat, and a spring pressed check valve disposed on said seat for controlling flow of fuel to said high pressure passage.

4. A burner nozzle comprising a hollow nozzle body having an open discharge end formed with a seat, a nozzle tip removably disposed in said seat and formed with a discharge orifice and a whirl chamber in communication with said orifice, said tip being also formed with separate inflow ducts for conducting low pressure and high pressure fuel to said chamber, said low pressure ducts being in the form of small slots provided on the inner surface of the tip, a hollow valve sleeve disposed within the nozzle body and spaced therefrom to provide a low pressure fuel passage, the end of said sleeve adjacent said tip seating flush against the inner surface of said tip and being formed with an annular axial groove in communication with said slots, the interior of said sleeve providing a flow passage for high pressure fuel leading to said high pressure ducts, means engaged between said sleeve and nozzle body beyond said low pressure flow passage for sealing of! the low and high pressure passages, said sleeve being formed with one or more ducts for comsure fuel passage leading to said low pressure municating the w pr passage W h said 5 4 axial groove, a valve sestlns sleeve removably dls- UNITED STATES PATENTS posed in said valve sleeve and formed with a now Number Nam Date passage and a Valve 7 for communicating fuel 214,394 Pfelfler et al Nov. 25, 1202 to ai s]: p u psssase. a d a p i pr ss 1,439,320 Home 1922 check 11mm 6 1,822,047 mask Sept. 8, 1931 GERALD 1,s7s,'za1 Nightingale Aug. 23, 1932 2,243,995 Alden June 3, 1941 2,249,434 Pearson July 15, 1941 REFERENCES CITED 2,254,123 Soaper Aug. 26, 1941 The following references are of record in the 2,436,815 L M 2, 1948 file of this patent: 2,483,951 Watson Oct. 4, 1949 

